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From: "cuzdav at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/111742] Misaligned generated code with MI using aligned
 virtual base
Date: Mon, 09 Oct 2023 17:50:06 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111742

--- Comment #2 from Chris Uzdavinis <cuzdav at gmail dot com> ---
No, this is not a ubsan report.
Code *crashes* and I thought showing the UBsan warning was enough to
demonstrate it.
A minimal change to make the code crash instead of just report ubsan errors:


struct X {
  void * a =3D nullptr;
  void * b =3D nullptr;
};

struct alignas(16) AlignedData { };

struct A : virtual AlignedData {
    int x =3D 0;       // << ********add this
  X xxx;
    int& ref =3D x;    // << ********and this
};

struct B : virtual AlignedData {};

struct Test : B, A {};

Test* t =3D new Test;

int main() {}


*** SEGFAULT ***

https://godbolt.org/z/f57vs7jxP=